Load tensioning and binding structures of the overcenter lever type heretofore have been provided in many different forms. These tensioning and binding structures include an actuating lever which may be swung slightly past a center position in one direction when in a load tensioning mode and well past the center position in the opposite direction when in the load releasing mode.
When high tensioning forces are desired to bind a load considerable force must be applied to the actuating lever thereof in order to swing the lever to its load tensioning position slightly past the center position and as the lever is swung slightly past the center position the lever has a tendency to "snap" from the center position to its limit position and this snap action can cause injury to the hand of a workman swinging the lever to the overcenter limit position thereof should a portion of his hand be caught between the approach side of the lever and the load being tensioned. In addition, when the lever is swung in the opposite direction through the center position, the lever tends to swing in a snap action toward the load releasing position. This snap action movement can cause injury to various body portions of a workman attempting to release a load tensioning and binding structure. Still further, load tensioning and binding structures of this type are also subject to inadvertent loosening by swinging movement of the levers from the slightly overcenter load tensioning positions to the release positions as a result of foreign objects striking the free end portions of the levers.
Accordingly, a need exists for an overcenter tensioning and binding lever structure which incorporates safety features that will prevent or at least greatly reduce the possibility of personal injury as a result of operation thereof and which will prevent or substantially eliminate any possibility of accidental loosening of the load tensioning and binding structure.
Examples of load tensioning and binding structures including some of the general structural and operational features of the instant invention are disclosed in U.S. Pat. Nos. 2,353,017, 2,449,600, 2,587,874, 2,821,359, 2,947,514 and 3,942,454.